John Ugelstad, Norwegian chemical engineer and inventor (born 1921)

John Ugelstad was a Norwegian chemical engineer and inventor, known for discovering a process to manufacture monodisperse micropellets or microbeads and dynabeads. He was a professor at the Norwegian Institute of Technology and consultant for DuPont.

April 3 is the 93rd day of the year in the Gregorian calendar; 272 days remain until the end of the year.